Human papillomaviruses (HPVs) are small DNA viruses that are the major cause of cervical cancer. Differentiation of the host keratinocyte is essential for productive infection, but the cellular factors involved are unknown. The HPV31 E2 protein is essential for the productive life cycle, but low expression and lack of antibodies has hampered studies of its function. Aim 1. The HPV31 E2 protein will be epitope tagged in the context of the complete viral genome and used to infect primary keratinocytes. The localization and expression of E2 throughout the productive life cycle and during differentiation will be determined. Aim 2. Cellular promoters regulated by E2 will be identified by chromatin immunoprecipitation followed by microarray analysis, and the effects of the products of these promoters on the viral life cycle will be determined. Aim 3. Cellular proteins that interact with E2 in differentiating keratinocytes will be identified using tandem affinity purification. The effect of these cellular factors on the productive viral life cycle will be determined. These studies will discover cellular factors used by the virus to propagate itself and how the virus manipulates the cell in the earliest stages of cancer development. [unreadable] [unreadable] [unreadable]